压力诱导的比斯穆托坦塔莱特 (BiTaO) 的相变:从单晶衍射和拉曼光谱学的洞察力
Luying Wang1, Dongzhou Zhang2, Maining Ma3
1School of Management, Guizhou University of Commerce, Guiyang 550014, China.
Inorganic chemistry
|March 12, 2025
概括
高压研究显示,甲 (BiTaO4) 经历可逆的相位过渡到更密集的正方形结构. 高压马相 (HP γ-BiTaO4) 显示显著的体积减少和增加的协调数.
科学领域:
- 矿物物理 矿物物理
- 材料科学 材料科学 材料科学
- 地质化学 地质化学
背景情况:
- 比斯穆托坦塔莱特 (BiTaO4) 是一种矿物质,在先进材料中具有潜在的应用.
- 了解其在极端压力下的行为对于地质学和材料科学方面至关重要.
- 在高压下对BiTaO4多态性的先前研究是有限的.
研究的目的:
- 为了研究天然 bismutotantalite (α-BiTaO4) 的高压相变.
- 描述与这些转变相关的结构和体积变化.
- 确定研究阶段的状态方程.
主要方法:
- 在现场高压单晶X射线衍射.
- 在现场高压拉曼光谱.
- 在不同压力下分析结构和体积数据.
主要成果:
- 在11.0-11.8 GPa时,α-BiTaO4可逆地转化为中间的正交相 (HP β-BiTaO4).
- 在13.9-14.4 GPa时,进一步过渡到更密集的正交相 (HP γ-BiTaO4) 发生.
- 与α-BiTaO4 (6) 相比,HP γ-BiTaO4 的体积崩率为6.2%,Bi/Ta 协调数量增加 (8/9).
- 确定了单元细胞参数和空间组 (HP β-BiTaO4 的 Fmm2,HP γ-BiTaO4 的 Pnma).
结论:
- 在高压下,石经历了显著的结构变化,形成更密集的相.
- 观测到的可逆相变和结构紧缩对理解地球深层内部的矿物行为有影响.
- 确定状态方程为地球物理建模和材料科学应用提供了关键数据.
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